Greg Lee said:

I took a selection of spices that were all
in the same type of bottle, closed my eyes, shuffled the bottles
around, and opened and sniffed them one by one, trying to identify
the spice by name. I was sure I could do it but was quite amazed to
discover that I couldn't do it at all.

IIRC the limit is 3 scents, after that the nose gets overloaded.