Your uncle is a very intelligent person and there is also a lot of Wisdom in whatever our ancestors have tried to tell us. So here are the two images, I guess we all know that Lakshmi is goddess of wealth and Saraswati is goddess of Knowledge and wisdom.
As you can see above, Lakshmi sits on Lotus, whereas Saraswati on a rock.
What this signifies is that money is like lotus, never sticks to a place and keeps moving around. You have it today, you may not tomorrow.
Saraswati sits on a rock, knowledge and wisdom is like that, once gained it stays with you forever.
So what your uncle is trying to say is, while trading (I'd say in every aspect of life) don't focus on chasing money. Earn knowledge and wisdom, money sitting on lotus will automatically follow you.
For me it resembles, lakshmi is looking like sideways trend, (both left two hands, head and right two hand). Perhaps it tells money is always sideways trend, it will come and then go and again will come,