Hebrews 11:1 Now faith is the substance of things hoped for, the evidence of things not seen.
The Greek word here translated "substance" is "hupostasis" and carries the connotation of a firm foundation. Faith is not a leap in the dark. It is based on reality - evidence - not just wishful thinking. Here are several variants in translation from other versions for the word "substance:"
I hope you have found this helpful.
God bless,
Mike