I'm trying to fathom what it might be like for a person with aphasia and for one with agnosia. For a person with a visual agnosia I wonder this: if two unrecognizable objects are shown to them, and one is entirely within the background of the other, (say a fork on a cutting board) do these two objects mold into a single unrecognizable object or do they remain distinct unrecognizable objects? Or have I got it all wrong and they don't even "see" any object to speak of (regardless of how many or how they are positioned)?
It all depends on how you define "language" and "thought". The way I define them (very broadly, really universally), neither can exist without the other.
Language is a component of thought, while thought produces language. Language and thought are so inter-dependent as to be virtually the same thing.
And at the social level, thought and language are commutative, so that at times one's language may serve to provoke others to think, while at other times one's thoughts may motivate one to express them in language, for purposes of communicating or sharing with others. And vice-versa.
Language and thought are also commutative on the personal, individual level, in that they help bridge the barriers between internal and external realities.
Perceptions on the other hand, are the mechanisms through which we gain the awareness we need to form thoughts and language. Neither thoughts nor language are possible without the ability to perceive on some level.
So in the order of primacy:
Perception or sense
Generic Ideas and language, often equally irrational
Reasoned logic and logical language (with increasing complexity)
Sound judgment or wisdom, and the ability to use language for good purposes (most complex)
I say "primacy" for this list, because perception (or sense) is the foundation for all thought and language, at any level. People can and often do compensate for losses of perceptual ability.
Update (I've been asked to provide references for the bases of my opinions). The following is from Stanford University's Center for the Study of Language and Information:
- What is the Language of Thought Hypothesis?
LOTH is an empirical thesis about the nature of thought and thinking. According to LOTH, thought and thinking are done in a mental language, i.e., in a symbolic system physically realized in the brain of the relevant organisms. In formulating LOTH, philosophers have in mind primarily the variety of thoughts known as ‘propositional attitudes’.
The Epistemology of Visual Thinking in Mathematics
5.2 An evidential use of visual experience in proving
Visual perception is used to tell in particular cases whether the rule thus expressed is correctly implemented...
We may distinguish two operations with respect to a given linguistic operation, in particular, a (declarative) sentence and its parts. The first operation is the analysis of the expression with the aim of understanding it, of grasping its meaning. The second operation consists in investigations concerning the factual situation referred to by the given expression. Its aim is the establishment of factual truth. This operation is not of a purely logical, but of an empirical, nature...Thus, for every expression that we can understand, there is the question of meaning and the question of actual application; therefore the expression has primarily an intension and secondarily an extension.
We shall define the term 'analytic' in such a way that it is applicable to all those sentences, and only those sentences, of Language II that are valid (true, correct) on the basis of logic and classical mathematics...The synthetic sentences are the (true or false) sentences about facts. An important point is that Language II includes descriptive symbols and hence also synthetic sentences.
...language evolved in two stages, and its main purpose was not communication—to show that the ability to think mathematically arose out of the same symbol-manipulating ability that was so crucial to the emergence of true language.
In conclusion, I have tried to show that thinking is enhanced by language. Even further, that conscious thought and logical mental processes are themselves a unique kind of language. Perception is the tool by which we prove ideas, whether true or false. Perception is also the tool by which we gain external information which is used in deduction.
I think the answer is a qualified yes, humans can think without language. Ultimately though it depends on what you mean by "think."
There is a remarkably large number of deaf people who are not exposed either to a signed or spoken language even in developed countries. These people often invent their own gesture systems, referred to as home sign systems. These people In these cases, the deaf children's systems are more complex than the gestures their parents use (Carrigan & Coppola, 2012). My dad was a home signer until after high school, and he learned how to work on his car, drove a motorcycle, and figured out how the furnace worked. Based on these examples, it is clearly possible to engage in fairly complex reasoning without language. In the article cited below, Spaepen et al. (2011) describe how home signers have some concept of number, albeit imprecise.
This is all to say that thinking is possible without language. Home signers are not catatonic, and can actually engage in complex reasoning. One the other hand, language is a huge cognitive advantage, and in this respect it certainly has an impact on thinking. Language facilitates transmission of information (learning), and it provides a way of organizing thought.
Carrigan, E. M., & Coppola, M. (2012). Mothers Do Not Drive Structure in Adult Homesign Systems: Evidence from Comprehension. In N. Miyake, D. Peebles, & RP Cooper,(Eds.), Proceedings of the 34th Annual Conference of the Cognitive Science Society (pp. 1398-1403).
Spaepen, E., Coppola, M., Spelke, E. S., Carey, S. E., & Goldin-Meadow, S. (2011). Number without a language model. Proceedings of the National Academy of Sciences, 108(8), 3163-3168.
It depends on the type of learning process of a person. One can be better at remembering images, so he might access the images first when trying to define an object/event/etc. This can be thought of as having a photographic memory.
The main reason why most people think with words is because it is a much more sophisticated and structured learning process, and is taught young. Missing the opportunity to learn a language when youre young would most likely cause them to develop a different way of processing information.
Same way goes for someone with visual agnosia. He might develop another way of recognizing objects. For example to use other senses (much like the blind uses his hands to "see"). So one with agnosia would have to use another approach to understand that the fork and the cutting board are two different objects.
Developing (with time or by injury) agnosia or aphasia at some point in your life would certainly mess your usual way of processing information; and it would be very hard to rebuild a new recognition system as old habits are hard to break.
On another note, some friend of mine claims that he consciously thinks with noises when playing and writing music.
It is hard to imagine what evidence might be found of thoughts existing without language. Even feral children encounter language (either verbal or nonverbal) through limited contact with people or animals, and lab animals communicate nonverbally with researchers, even if only through their environments (the researcher observes the animal's behavior, and the animal observes how the researcher changes its environment, e.g., its food, waste, and cage furnishings). For reasons such as these, the prospect of thought without language may be somewhat untestable. Producing a sentient being that is never allowed the opportunity to communicate with others would also be unethical by most means I can imagine.
As for your (largely unrelated) question about object discrimination in the absence of recognition, I can't offer any insight in the context of visual agnosia per se, other than to point out that (according to Wikipedia), "Visual agnosia...is not due to a deficit in...language." However, outside that context, I would recommend watching an episode of Scientific American Frontiers, "The Man with Two Brains" that I mentioned in another answer of mine just yesterday! The effects of lacking communication between one's cerebral hemispheres are different from visual agnosia, but give some insight into how unknown objects (e.g., crude drawings) may be identified and differentiated in the absence of linguistic function, which is generally left-hemisphere-dominant. In this episode, Mike Gazzaniga also demonstrates how his split-brain case study subject attends differently to the components that comprise larger objects vs. the overall unity of those objects as one meta-object (coined here for lack of a better term), depending on which hemisphere's visual field processes such an object comprised of smaller objects. The left hemisphere, in which linguistic functions primarily operate, tends to break down these meta-objects and perceive them separately, whereas the right hemisphere tends to notice mostly the overall silhouette of the meta-object. Thus when a still-life painting of a pile of objects that together resemble a face is presented to the right (relatively non-linguistic) hemisphere, a face is perceived, not a bunch of objects (that happen to be organized in a face-resembling pattern).
This sort of evidence might offer the next-best thing to what you'd hope to find through study of visual agnosia. From Gazzaniga's demonstrations with his split-brain case study subject, it seems likely that, without involving the left hemisphere (and thus largely avoiding the involvement of major linguistic processes), the right hemisphere operating alone would perceive a fork on a cutting board as one object in the shape of a cutting board, or would at least require stronger visual contrasts between the two (e.g., color, shadow, texture) to achieve a just-noticeable difference between the two, relative to the left hemisphere operating without the right. Whether that actually has anything to do with language though, or whether it's a separate qualitative difference in the functions of each hemisphere's visual processes, is another question on which I can hardly even begin to speculate.
Yes, Thinking without language is possible. Suppose a well-known boy "Mogli" who was left alone in jungle before he could learn language from his parents. But still he could manage to live many years in jungle till he met other humans. Mogli may be a fictional character but story is based on real incidence and much this kind of cases has been recorded.
My point is, in absence of language the jungle boy was able to learn things, think which is good and bad. Make strategies and learned how to use objects. His learning was beyond natural instincts. Without thought or cognitive processes it would not be possible to live throughout these many years. When these kinds of kids are adopted again by humans they learned how to use their vocal cords, modulate voices, and understand gestures. During this learning they think and finally they learn to use language to express their thoughts.
Yes, I do think thinking without language is possible. A pretty simple example is the word 'perceive'. A person may perceive a lot many phenomena even if s/he doesn't know how to put it in words.
To me Leonardo Da Vinci seems to be a great thinker who used to think without language, evident by his ability to develop a fly-able sketch without accompanying language of aviation. This is to be understood in the context that every field of specialty has its own language and even then time and again there are prodigies who deny this language and add value to the specialty. If logic and proof is the language of Mathematics then Srinivas Ramanujan thought without that language thereby finding it difficult to provide proofs to his formulas and theorems.
Language is basically a digitised construct of an analogous world. If one were to think based only on words , s/he might never be able to perceive the reality of the world. This is evident in Einstein's statement, “Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.” Here, Einstein might be seen referring to knowledge as known by language and words and imagination as an ability to think beyond these words. Einstein's inability or blessing to have not been able to speak till age of seven ( Edit: http://www.albert-einstein.org/article_handicap.html ) might be reason behind his 'superpower' to look beyond words.
To cite a more orientalist example, Indian meditative sages are supposed to have pretty sharp contemplative skills using mediation. (Edit : http://newsroom.ucla.edu/releases/evidence-builds-that-meditation-230237 ) As a personal experience, which most Indians can relate to, meditating on a situation is much more helpful than trying to fit it into the maze of language. ( Edit : can't cite a study to showcase experiences of people around me, but to me more precise I have had many teachers who would tell us to just meditate over a new concept if the words are enough, and it has helped many students including me)