Solaris is too vague to call it an exploration of the idea imo. Lem postulates that there is an intelligence so different to ours that it's incomprehensible. Naturally he can't describe it in any but the most nebulous terms. It remains a postulation without any supporting arguments that such a form of intelligence is realistic.

If you mean the Book written by Stanislav Lem, i did read that but i don't understand how you connect the Ocean with "not having the concept of numbers".