Intellect can develop ITSELF - in essence - no company of others is necessary. Only the intent and motivation of the intellect ITSELF is needed.
There is enough to learn just by studying our own body and trying to learn to control its functions. Can you consciously control your heartbeat? Can you slow and stop breathing? What about body temperature? What about separating our consciousness from our physical body? Why not?
Also, by experiencing extreme loneliness - an ascetic can learn to understand initial MOTIVES of the Great Intellect for creating the Universe.
Since we are not truly alone, ascetics who develop telepatic communication skills can actually assist great number of people without moving from their "mountain".