I think you mean that it would not have found it using the human's memory. "On" does not work. "By" works, but "using" is clearer: There is no way I could have found the way by the human's memory alone.
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AnonymousWould you never say in any context 'on memory alone'?Yes, but not the context you have there. "I could not find it depending on memory alone."
AnonymousIt is right if you put 'depending' ? and without it? I could not find it depending on memory alone."I must confess I can't come up with an example that uses "on memory", but I can see nothing to rule it out in the right setting.