العالم
كلمة (عالم) في اللغة اسم فاعل من الفعل (عَلِمَ يَعلَمُ) والعلم...
‘Abdullāh ibn ‘Abbās (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Were people to be given everything that they claimed, some men would (unjustly) claim the properties and blood of (other) people. However, the onus of proof is on the plaintiff and the oath is upon the one who denies the claim."
شرح الحديث :
This Hadīth establishes the principle of not accepting claims that are void of proofs and evidence, as well as making the defendant who denies the claim take an oath, in order to fulfill justice and establish the truth and protect lives and properties. So, whoever makes a claim that lacks proof, his claim is rejected, whether it is related to rights and transactions or to matters of faith and knowledge.