If there were no bad goods in the world,
Every fool might be a skilful merchant;
For then the hard art of judging goods would be easy.
If there were no faults, one man could judge as well as another.
Again, if all were faulty, skill would be profitless.
If all wood were common, there would be no aloes.
He who accepts everything as true is a fool,
But he who says all is false is a knave.
 Rumi, Masnavi (1273). copy citation

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Author Rumi
Source Masnavi
Topic skill art
Date 1273
Language English
Reference Masnavi, Book II
Note Translated by Edward Henry Whinfield
Weblink https://en.wikisource.org/wiki/Masnavi_I_Ma'navi/Book_II

Context

“Nor yet is every night quite void of power. In the crowd of rag-wearers there is but one Faqir; 5 Search well and find out that true one. Tell the wary and discerning believer To distinguish the king from the beggar. If there were no bad goods in the world, Every fool might be a skilful merchant; For then the hard art of judging goods would be easy. If there were no faults, one man could judge as well as another. Again, if all were faulty, skill would be profitless. If all wood were common, there would be no aloes. He who accepts everything as true is a fool, But he who says all is false is a knave. NOTES: 1. See Koran xi. 63. 2. Koran ix. 108. 3. This is a proverb ascribed to Ali. It means, people are always losing wisdom and seeking it like a lost camel (Freytag, Arabum Proverbia, i. p. 385) .” source