diff --git a/rgbAI/lib/func.py b/rgbAI/lib/func.py
index c47e1a8..e6fb8fe 100644
--- a/rgbAI/lib/func.py
+++ b/rgbAI/lib/func.py
@@ -39,7 +39,11 @@ class AIlib:
             if( layerIndex < maxLayer ):
                 return AIlib.think( layer, weights, bias, layerIndex + 1 )
             else:
-                return np.squeeze(np.asarray(layer))
+                out = np.squeeze(np.asarray(layer))
+                print("-Result-")
+                print(out)
+                print("\n")
+                return out
 
         except (ValueError, IndexError) as err:
             print("\n---------")
@@ -47,9 +51,32 @@ class AIlib:
             print( "Layer index: " + str(layerIndex) )
             print( "Max layer index: " + str(maxLayer) )
 
-    def gradient( cost1:float, cost2:float, inp1:np.array, inp2:np.array ):
-        dY = np.asarray(cost2 - cost1)
-        dX = np.asarray(inp2 - inp1)
-        print(dY, dX)
-        return dY / dX
+    def gradient( dCost:float, prop:list ):
+        propLen = len(prop)
+        print("PropLEN: ", propLen)
+        print(prop)
+        print("\n")
+        gradient = [None] * propLen
+        for i in range( propLen ):
+            gradient[i] = dCost / prop[i]
+
+        return gradient
+
+    def learn( inp:np.array, weights:list, bias:list, theta:float ):
+        # Calculate the derivative for:
+        # Cost in respect to weights
+        # Cost in respect to biases
+
+        res1 = AIlib.think( inp, weights, bias ) # Think the first result
+        cost1 = AIlib.calcCost( inp, res1 ) # Calculate the cost of the thought result
+
+        inp2 = np.asarray( inp + theta ) # make the new input with `theta` as diff
+        res2 = AIlib.think( inp2, weights, bias ) # Think the second result
+        cost2 = AIlib.calcCost( inp2, res2 ) # Calculate the cost
+
+        dCost = cost2 - cost1 # get the difference
+
+        weightDer = AIlib.gradient( dCost, weights )
+        biasDer = AIlib.gradient( dCost, bias )
 
+        print(weightDer, len(weightDer))
diff --git a/rgbAI/main.py b/rgbAI/main.py
index 587adf5..8687524 100755
--- a/rgbAI/main.py
+++ b/rgbAI/main.py
@@ -25,8 +25,8 @@ class rgb(object):
         # Cost needs to get to 0, we can figure out this with backpropagation
         return cost
 
-    def learn():
-        print("learn")
+    def learn( self, inp:np.array, theta:float ):
+        ai.learn( inp, self.weights, self.bias, theta )
 
     def think(self, inp:np.array):
         print("-----Gen " + str(self.generation) + "------")
@@ -45,19 +45,6 @@ def init(): # init
     bot = rgb()
 
     inpArr = np.array( [0.2, 0.4, 0.8] )
-    res = bot.think( inpArr )
-
-    cost = bot.calcError(inpArr, res)
-    print("Cost: " + str(cost))
-
-    inpArr2 = np.array([0.3, 0.5, 0.9])
-    res2 = bot.think(inpArr2)
-    cost2 = bot.calcError(inpArr2, res2)
-    print("Cost: " + str(cost2))
-    print("\n----")
-
-    print("Gradient\n")
-    gradient = ai.gradient( cost, cost2, inpArr, inpArr2 )
-    print(gradient)
+    bot.learn( inpArr, 0.1 )
 
 init()