text: **Deductive**
  A deductively valid argument is one whose premises guarantee the truth of its conclusion.[11] For 
  instance, the argument "(1) all frogs are amphibians; (2) no cats are amphibians; (3) therefore no cats are 
  frogs" is deductively valid. For deductive validity, it does not matter whether the premises or the 
  conclusion are actually true. So the argument "(1) all frogs are mammals; (2) no cats are mammals; (3) 
  therefore no cats are frogs" is also valid because the conclusion follows necessarily from the premises.[65] 
  
  According to an influential view by Alfred Tarski, deductive arguments have three essential features: (1) 
  they are formal, i.e. they depend only on the form of the premises and the conclusion; (2) they are a 
  priori, i.e. no sense experience is needed to determine whether they obtain; (3) they are modal, i.e. that 
  they hold by logical necessity for the given propositions, independent of any other circumstances.[66] 
  
  Because of the first feature, the focus on formality, deductive inference is usually identified with rules of 
  inference.[67] Rules of inference specify the form of the premises and the conclusion: how they have to be 
  structured for the inference to be valid. Arguments that do not follow any rule of inference are 
  deductively invalid.[68] The modus ponens is a prominent rule of inference. It has the form "*p*; if*p*, then 
  *q*; therefore*q*".[69] Knowing that it has just rained ( ) and that after rain the streets are wet ( 
  ), one 
  can use modus ponens to deduce that the streets are wet ( ).[70] 