1) Economic expert 2) Economist 3) Population-study pioneer 4) Thomas malthus 5) Thomas robert malthus 
[demon] In demonology, Malthus (also Halphas, Malthas, or Malthous) is an Earl of Hell, commanding 26 legions of demons, who is said to have a rough voice when speaking. He is often depicted in the shape of a stork. Malthus builds towers and fills them with ammunition and weapons, an armorer of sorts. He is a prince of Hell. He is also said...
[n] - an English economist who argued that increases in population would outgrow increases in the means of subsistence (1766-1834)
Thomas Malthus noun an English economist who argued that increases in population would outgrow increases in the means of subsistence (1766-1834)