While it is practically impossible to imagine, how it would be to have no senses at all, we would still have a mind. And even though this mind perceives nothing of the outside world, it would still perceive itself. And so it would know of itself. Therefore, it is possible to gain knowledge without senses.
Right now, no way in hell we could gain knowledge other than through the senses.... In the future though if telekinesis or whatever the word for communication straight from one's brain to another brain is comes a thing, then and only then could it be possible to gain knowledge other then through the senses...... But I doubt thats going to be an option for roughly another century..... Or two
Human beings differ from animals in so many different aspects. Are our senses even reliable? Is reason even reliable? We can't rely simply on these things to gain knowledge and wisdom (two very different things). Humans have emotions, which no one can dispute, and we can't say "don't trust feelings or emotions" because it's essential to all humans. Humans have choice, and are self aware, and can remember their past, and empathize with others. We can't deny those parts of ourselves because they make us who we are. We learn from them and grow.
The knowledge you get by your senses is called empiric knowledge. It is based on your perception of nature, which can be different of my own. Senses are illusory, and what they observe may or may not correspond to reality. In fact, the only way to acquire real knowledge is deduction. You use only reason, without participation of your senses, and get to the truth of things, like mathematics.
Your brain can only gather data through hearing, sight, smell, taste, and touch. Other than that, you have no other sensory input. Your brain functions by by using the data gathered by your senses to operate how you run your thoughts. How else do you think that you would gain data?
Any information we have about the world comes from the world itself. And the only way to get that information is through the senses. If it seems that this is just too obvious, well, I think so, but I'm looking for some other ideas to change my opinion. What else isothere but experience?
If you were to gain new information otherwise -- ie. Divine revelation or telepathy -- you would still have the task of verifying its accuracy ahead of you. You would know what the revelation, or telepathic transmission, TOLD you but you could not claim that content, itself, to be knowledge.
Without feeling, smelling, tasting, seeing, and hearing, we would never be able to learn anything. No one can speak to us, and we cannot read. We would grow up not knowing language or what anything looks like, so we could not be able to think. Even if we were to take our senses away today, we would still be able to think and therefore have knowledge, but there would be no way to gain knowledge.
Without sensory input, it's impossible for the brain to collect information about the body and about the environment. Sensory reception is the only way anything about the world can be understood. Take away our ability to touch (feel), see, hear, taste, and smell and it would be equivalent to not existing from our point of view.
You can't fabricate knowledge out of nothing. It's impossible to deduce any knowledge without thing from which you can deduce. It's like trying to build something without any materials. For example, what's a triangle if you don't know what a line or angle is? You need a foundation from which you can make deductions from and, assuming that one is born without knowledge, the only way to have such a foundation is to build it from sensory experiences.